Tube Practice Amp Adding Reverb

[Chuck H]

It hasn't been indicated whether the Kustom is a head or combo amp. I assumed a head since all the K### amps I've encountered were heads. I'm not sure if there's an imperative for one package portability. It's been hinted at. But this would not be a difficult rig to understand or manage, there would be no need to build a reverb circuit and the tremolo is preserved.

A few resistors and a used signal processor and bada bing. The Silvertone could be used as a little amp with the flip of a switch

[Wolfman88]

It hasn't been indicated whether the Kustom is a head or combo amp. I assumed a head since all the K### amps I've encountered were heads. I'm not sure if there's an imperative for one package portability. It's been hinted at. But this would not be a difficult rig to understand or manage, there would be no need to build a reverb circuit and the tremolo is preserved.

A few resistors and a used signal processor and bada bing. The Silvertone could be used as a little amp with the flip of a switch

So with this drawing you're saying use the output of the Silvertone to run the reverb tank? The K100 is a 50 watt head plugged into a 8 ohm 2 12 cab.

[Chuck H]

The output of the Silvertone would be doped down to provide a suitable signal to feed any outboard effects. Not a reverb pan. Most outboard effects units include reverb or you could get a dedicated reverb effect (like an Alesis Quadreverb, etc.). The way I see it a decent used effects unit or reverb unit would cost about the same as building a reverb unit from a pan. We have not yet determined if the board you have is a driver, recovery or both. Or if it even works. Further, we do not know it's specs to allocate it to the circuits. Further, the reverb pans you have are not suitable to drive from the output of the Silvertone. One has a high input impedance and the other, the one you have a board for is demonstrating a shorted input transducer.

If you look at the drawing you'll see that the box I've located atop the Kustom says "effects unit/reverb". An effects unit is an effects unit. And a reverb is a reverb. Not a reverb pan. I tried to imply by scale that it would be something like a Digitech, Alesis, BOSS, etc. Not a reverb pan. Though you could drive a reverb pan with the Silvertone it would be one you'd have to buy. And then you would need to amplify the output of that pan to make it useful. Some here have suggested that you could rewire the tremolo circuit for this. I'll tell you why I think that's a bad idea. You would not be adding reverb to the Silvertone. You would be driving a reverb pan with the Silvertone output and then amplifying the pans output with a tube in the Silvertone so that it could be sent to another amp. But you could never make it an integrated part of the Silvertone as an independent unit because of feedback loop issues that are too complicated to adequately cover here. I also think that the technical aspects are beyond your experience level.

In the diagram above it simply operates like this...

The Silvertone is a preamp. You can plug anything into the input that you would plug into any amp input. The line between the Silvertone and the Kustom is like an effects loop. You can plug anything between the Silvertone and Kustom that you would plug into any other amps effects loop (including a reverb but NOT a reverb pan). Get it?

[Wolfman88]

Like I said in a earlier post the board is everything the tank needs preamp/driver and recovery circuit. If I could get a 25vdc to it it would be everything I need I need a 25vdc power supply for it and figure out where to put the reverb level pot. Like I said before I know it works because the reverb was one of the few things that worked on that organ. I need to know how to power it I would like to have a separate power supply rather than wiring it in the Kustom as said before basically making it a stand alone unit.

[Chuck H]

Like I said in a earlier post the board is everything the tank needs preamp/driver and recovery circuit. If I could get a 25vdc to it it would be everything I need I need a 25vdc power supply for it and figure out where to put the reverb level pot. Like I said before I know it works because the reverb was one of the few things that worked on that organ. I need to know how to power it I would like to have a separate power supply rather than wiring it in the Kustom as said before basically making it a stand alone unit.

A plain 12V/3A power transformer could be used. Readily available almost anywhere. You would wire it with voltage doubler rectification. I didn't feel like drawing it up this time so I just grabbed this on an image search. It looks fine. You'll need to figure out the schematic AT LEAST enough to wire this. It's as simple as it gets.

You obviously don't need to use a 230V primary transformer. You would use a transformer made for whatever your wall voltage is.

[nickb]

An 18V transformer would be easier as no doubler required. Or even easier a 24VDC wall wart.

[Chuck H]

An !8V transformer would be easier as no doubler required. Or even easier a 24VDC wall wart.

I didn't assume a wal wart would have the current. But I just looked some up and 2500mA is pretty common. I think that should do it.

[g1]

An 18V transformer would be easier as no doubler required. Or even easier a 24VDC wall wart.

How is that even a doubler? Looks like standard split supply to me.
And wouldn't it be +/-12 rather than +/-24 out?

[nickb]

How is that even a doubler? Looks like standard split supply to me.
And wouldn't it be +/-12 rather than +/-24 out?

What Chuck drew is a doubler. It has a 12V winding and nominally 24V out ( actually more like 30V). A split supply has a center-tapped transformer.

[g1]

What Chuck drew is a doubler. It has a 12V winding and nominally 24V out ( actually more like 30V)

In Chuck's defense, he said he didn't draw it, that's why I figured it was fair game.
Note the missing caps coming off the transformer.
Here's one on the right:

[Dave H]

Note the missing caps coming off the transformer.
Here's one on the right:

The one on the right is a quadrupler (two stacked half wave doublers)

[Dave H]

How is that even a doubler? Looks like standard split supply to me.

It's a doubler but I think the bottom two diodes of the bridge are redundant. They will always be reverse biased.

[Chuck H]

For the record, I did not design the circuit. I just grabbed it with a search. It looked alright to me. I have no idea if Wolf's board requires +/- rails so I played safe. I already have too much time into this thread for the result so maybe I'm getting lazy

[nickb]

In Chuck's defense, he said he didn't draw it, that's why I figured it was fair game.
Note the missing caps coming off the transformer.
Here's one on the right:

I guess it's a matter of definition. Getting double the voltage out qualifies it as doubling to me. The figure on the right is actually a quadrupler.

[Chuck H]

I believe the one I posted is actually a sort of dual rail doubler (?) for the +/- rails and just looks very bridge like because the diode junction happens to be convenient with the caps doing double duty for either polarity.?. I'm not as good with power supplies as I probably should be by now, but I think this is what I see.